A parking lot south of AT&T Park and China Basin is seen in San Francisco, Calif., on Wednesday, March 24, 2010. Rumors are circulating that a new basketball arena could be built on the site which could be a new home for the Golden State Warriors if the NBA team is sold.

Potential buyers of the team have asked the San Francisco Giants about building a state-of-the-art arena in Mission Bay, south of AT&T Park, sources say.

The team is on the verge of finishing an agreement that would give the Giants exclusive negotiating rights with the Port Commission to develop the parking lot behind AT&T Park. So if you want to talk about an arena in what the team is calling the Mission Rock District, you need to speak to the Giants.

The Giants have already mapped out an ambitious plan to develop the area that calls for an urban community with a pedestrian walkway and retail stores extending all the way to the bay. Their proposal even includes a 5,000- to 7,000-seat arena.

Granted, a 20,000-seat arena would be a departure from the current plans, but the land the Giants plan to develop is probably the best and only place in San Francisco for a major arena.

The Giants are militantly silent on the topic, issuing a curt "no comment" when asked about the subject.

But the idea makes too much sense not to consider. It starts with the announcement Monday that current Warriors owner Chris Cohan is willing to sell the franchise. Potential new owners are already lining up. (Don't think the only choice is Oracle Corp. CEO Larry Ellison, who recently expressed interest. A group fronted by NBA Hall of Famer Jerry West is also in play.)

Any new ownership group would be foolish not to look at San Francisco. In the mid-'80s, then-Warriors President Dan Finnane commissioned a study to determine the financial effect of moving to the city. The result was a 30 percent increase in value and revenue.

Today that number would only be higher. The sponsorship opportunities would be much better, the potential for selling premium tickets would be higher, and selling the naming rights to the new arena would be a cinch. In Oakland, after the poor Warriors renovated their arena in 1996, the facility was referred to as (Your Name Here) Arena for years before Ellison's Oracle finally signed up in 2006.

There are some hurdles. The Warriors' current lease with the Oakland-Alameda County Sports Authority expires in 2027. However, there is reportedly an out clause in 2017. It would take a chunk of money, maybe $60 million, to exercise it. But if someone did, seven years to design and build a new facility is just about perfect.

Redesigning the plans for Mission Rock to include a major arena would be difficult, but not insurmountable.

"It's not what was in the proposal, that's for sure," said Jonathan Stern, San Francisco's assistant deputy director for waterfront development programs. "It would be a completely different land use than what has been thought of to date."

The Giants would have to craft an entirely new plan. But if they do, it would have the potential to be a terrific addition to what is currently a parking lot and under-utilized shoreline.

The city should enthusiastically embrace the idea. Not only could the team be the San Francisco Warriors again, as they were from 1962 to 1971, a major new facility would be a boon to downtown. Today, when huge touring performers like Madonna or Barbra Streisand come to the Bay Area, they appear at HP Pavilion in San Jose or in Oakland.

The city has a modest selection of alternatives. There's Masonic Auditorium, which is small and in the midst of a residential neighborhood, Bill Graham Civic Auditorium, which has seen better days, and the Cow Palace, which is a great place for a rodeo.

There are questions about the fans, of course.

"My question would be, are you moving away from your fan base?" said Finnane, who is retired.

Long known as one of the league's most loyal, albeit long-suffering, fan bases, East Bay fans would probably be willing to ride BART across the bay. The area is a nexus for public transit. Even after 10 years, the Giants are still able to say that 50 percent of their fans come to AT&T Park by some means other than a car.

There's a long way to go before this happens, but you've got to love the concept. A few years ago, the team printed up the classic jersey from the San Francisco days. On the back was a cable car and on the front it simply said "The City." They weren't talking about Oakland.